Alloying engineering for thermoelectric performance enhancement in p-type skutterudites with synergistic carrier concentration optimization and thermal conductivity reduction  

作　　者：Zhiyuan Liu Yonggui Wang Ting Yang Zuju Ma Huiyan Zhang Hailing Li Ailin Xia 

机构地区：[1]Key Laboratory of Green Fabrication and Surface Technology of Advanced Metal Materials,Ministry of Education,Anhui University of Technology,Maanshan 243002,China [2]School of Materials Science and Engineering,Anhui University of Technology,Maanshan 243002,China [3]School of Environmental and Materials Engineering,Yantai University,Yantai 264005,China

出　　处：《Journal of Advanced Ceramics》2023年第3期539-552,共14页先进陶瓷（英文）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.51872006,and 22273081)and Anhui Province Natural Science Foundation for Excellent Youth Scholars(Grant No.2208085Y17).

摘　　要：The enhancements in thermoelectric(TE)performances of p-type skutterudites are usually limited due to the relatively low Seebeck coefficients owing to the higher carrier concentration and more impurity phases induced by inherent structural instability of a Fe-based skutterudite.As shown in this study,alloying engineering of Ni doping at Fe sites in a p-type CeFe_(3.8)Co_(0.2)Sb_(12)skutterudite can not only reduce the impurity phases with high thermal conductivity but also regulate the carrier concentration,and thus significantly increase the Seebeck coefficient.The thermal conductivity was largely suppressed due to the enhanced point defect phonon scattering and decreased hole concentration.As a result,a TE figure of merit ZT of the CeFe_(3.5)Ni_(0.3)Co_(0.2)Sb_(12)sample reached 0.8,which is approximately 50%higher than that of a Ni-free sample.Appropriate Ni doping can maintain a high ZT at a high temperature by controlling the reduction in a band gap.Therefore,a high average ZT close to 0.8 at 650–800 K for CeFe_(3.5)Ni_(0.3)Co_(0.2)Sb_(12)was obtained,which was comparable to or even higher than those of the reported Ce-filled Fe-based skutterudites due to the synergistic optimization of electrical and thermal performances.This study provides a strategy to synergistically optimize electrical–thermal performances of the p-type skutterudites by alloying engineering.

关 键 词：p-type skutterudite materials Ni doping synergistic optimization thermoelectric(TE)properties 

分 类 号：TB34[一般工业技术—材料科学与工程]